1. Field of the Invention
The present invention relates to a connector for a cartridge of electronic parts such as a toner cartridge, for example, a toner cartridge incorporated into a copier, facsimile terminal equipment or printer.
2. Description of the Related Art
In general, an image forming apparatus is provided with a function of letting a user of the image forming apparatus know that the renewal time of a toner cartridge has come. Commonly, when the toner cartridge is attached to the image forming apparatus, a counter to count the number of times of image formation is reset. The number of times of image formation is integrated by the counter on the image forming apparatus side. When this number of times of image formation has reached a predetermined value, a command is displayed on an operation display so that the toner cartridge can be replaced with a new one.
In the image forming apparatus, a quantity of toner supplied to a developing device is controlled according to the concentration of toner accommodated in a toner cartridge, so that an image of high quality can be formed on a sheet of paper at all times. Therefore, it is necessary that a quantity of residual toner in the toner cartridge is accurately grasped. This quantity of residual toner is calculated by giving consideration to the number of times of image formation, which is counted by the above counter, and the size of a sheet of paper.
In this connection, in some cases, a toner cartridge, the life of which has not been fulfilled yet, is once detached from an image forming apparatus for the purpose of maintenance and then attached to the image forming apparatus again. In this case, since the counter to count the number of times of image formation is reset, it is impossible to accurately judge the life of the toner cartridge and the quantity of residual toner.
Recently, the market is infested with imitation articles made by the third parties. When these imitation articles are used, toner of low quality is supplied to the image forming apparatus. As a result, it is impossible for the image forming apparatus to exhibit the normal performance, and further the image forming apparatus might become out of order.
Therefore, the present inventors have devised that a memory to store various information is housed in the connector on the toner cartridge side. However, in this case, the following problems may be encountered. In the case of a commonly used connector housing of one piece structure, it is very difficult to arrange a circuit board including a memory in the housing, and further it is very difficult to assemble the connector.
The present invention has been accomplished in view of the above circumstances. It is an object of the present invention to provide a connector for a cartridge of electronic parts such as a toner cartridge which can be easily assembled.
In order to accomplish the above object, a first aspect of the invention provides a connector for a cartridge of electronic parts, which is a plug type connector fixed to a side plate of the cartridge of electronic parts,including: a plug housing having a back face opposing to the side plate of the cartridge of electronic parts; a cover housing combined with the plug housing; and a circuit board held by both the housings.
If the housing is composed of one piece, the structure in which the circuit board is laid out in the housing is restricted. However, according to the present structure, the housing is composed of two pieces. Therefore, the freedom of layout of the circuit board is enhanced, and the assembling can be easily carried out. When the number of times of image formation and the information about a quantity of residual toner are stored in the memory mounted on the circuit board housed in the connector, even if the cartridge of electronic parts is detached before the life of the cartridge is fulfilled and the cartridge of electronic parts is attached again, it is possible to accurately grasp the life of the cartridge of electronic parts and the quantity of residual toner. Further, when ID number is stored in the memory, it is possible to distinguish an imitation article from a true article. Therefore, it is possible to avoid using the imitation article. In this connection, the cartridge of electronic parts may be a single body. Alternatively, the cartridge of electronic parts may be composed of a unit in which other components of the image forming apparatus are integrated.
A second aspect of the invention provides a connector for a cartridge of electronic parts according to the first aspect of the invention, wherein the plug housing and the cover housing are combined with each other being relatively slid in a direction parallel with a surface of the circuit board. In this structure, the components can be easily assembled by a sliding assembling motion.
A third aspect of the invention provides a connector for a cartridge of electronic parts according to the second aspect of the invention, wherein the cover housing includes guide grooves to guide a sliding motion of the plug housing, and edge sections of the circuit board and edge sections of the plug housing are slid in the guide grooves. In this structure, the components can be easily assembled by a sliding assembling motion. Further, since edge sections of the circuit board and the plug housing are inserted into the guide grooves, the mechanical strength of combination of both the housings is high, and both the housings are so tightly combined with each other that the intrusion of toner into the housing can be prevented.
The invention described as a fourth aspect of the invention provides a connector for a cartridge of electronic parts according to the first aspect of the invention, wherein the circuit board is connected with the plug housing in such a manner that the circuit board covers an open portion of the plug housing, and a closed cross-section is formed by the circuit board and the plug housing. In this structure, the circuit board functions as a wall section of the plug housing. Therefore, the structural strength can be ensured.
The invention described as a fifth aspect of the invention provides a connector for a cartridge of electronic parts according to one of the first to fourth aspect of the invention, wherein a unit including the plug housing, circuit board and contacts is incorporated into the cover housing. When the components are integrated into a unit, the assembling can be easily carried out.
The invention described as a sixth aspect of the invention provides a connector for a cartridge of electronic parts according to the fifth aspect of the invention, wherein a forward end of a holding member to hold the circuit board and an exposed end portion of a lead penetrating the circuit board are located on the substantially same face as the back face of the plug housing, and they are located at the most backward position of the unit. According to the present structure, it is possible to conduct automatic mounting in which the leads of contacts and others can be automatically soldered to the circuit board in a dip tank.
The invention described as a seventh aspect of the invention provides a connector for a cartridge of electronic parts according to the sixth aspect of the invention, wherein the cover housing is provided with a protruding section for attaching to the cartridge of electronic parts. In this structure, the protruding portion which protrudes backward is arranged on the cover housing side. Due to the foregoing, the automatic mounting can be substantially realized when the back of the unit to which the circuit board is attached is made flat.
The invention described as an eighth aspect of the invention provides a connector for a cartridge of electronic parts according to one of the first to seventh aspect of the invention, wherein a lock section for locking both the plug housing and the cover housing, which are combined with each other, is arranged in a space surrounded by the plug housing and the cover housing. In this structure, what is called an inner lock structure is adopted. Therefore, when both housings are once combined with each other, they are not disconnected from each other even if a shock is given to them.